Kondo effect in the seven-orbital Anderson model hybridized with Γ8 conduction electrons

We clarify the two-channel Kondo effect in the seven-orbital Anderson model hybridized with Γ8 conduction electrons by employing a numerical renormalization group method. From the numerical analysis for the case with two local f electrons, corresponding to Pr3+ or U4+ ion, we confirm that a residual entropy of 0.5log2, a characteristic of two-channel Kondo phenomena, appears for the local Γ3 non-Kramers doublet state. For further understanding on the Γ3 state, the effective model is constructed on the basis of a j-j coupling scheme. Then, we rediscover the two-channel s-d model concerning quadrupole degrees of freedom. Finally, we briefly introduce our recent result on the two-channel Kondo effect for the case with three local f electrons.